Fresh elderflowers are extremely perishable and should be used soon after harvest.
Elderflowers can be held for a day or two in the refrigerator, but the aroma disappears fast. During refrigeration, store the flower in a container with a loose, breathable covering that allows excessive moisture to escape.
For longer storage, elderflower should be dried. Elderflowers do not freeze well.
Dried flower
To dry, remove fresh flowers from their stems, spread the flowers in thin layers on dehydrator screens, and dry at 95 F / 32 C for 12-14 hours. The flowers are sufficiently dry when the blossoms feel dry and slightly crisp if gently rolled and pressed between the fingers.
Store dried elderflower in an air-tight container away from light and heat. For best flavor and aroma, use elderflower within about 1 year after harvest.
The chemical compounds that create elderflower’s delicately sweet floral aroma will fade in storage, but other beneficial chemicals may stay fairly stable for up to 2 years. (1)
Ideas for use
Elderflowers are fully edible. Fresh flowers can be folded into a light batter and fried into a sweet, fragrant fritter. A few fresh blossoms can be sparingly scattered over a frosted cake or on top of iced or hot tea or other drink.
The flowers, whether dry or fresh, can be steeped by themselves to make a caffeine-free golden yellow tea or included in herbal tea blends. Dried flowers will quickly reconstitute in hot tea and look almost as pretty as fresh.
The classic use of elderflowers is for making elderflower cordial — a simple syrup of water and sugar infused with fresh elder flowers and lemon. The flowers leave their distinctive aroma and golden yellow pollen in the syrup.
This pale yellow cordial can be used in alcoholic mixed drinks, hot or iced tea, and cake frosting. It can be diluted with sparkling water to make a refreshing spritzer.
Weights and volumes
1 ounce by weight of dried elderflower measures a generous 1 cup.
1 ounce by weight of dried elderflower is equivalent to about 5 cups of fresh, de-stemmed flowers that have been gently packed.
Notes:
(1) Kaack, K & Christensen, L.P. (2010). Phenolic Acids and Flavonoids in Tea Processed from Flowers of Black Elder (Sambucus nigra L.) Stored in Different Packing Materials. European Journal of Horticultural Science. 75. 214-220.